Pruning Hydrangeas
About a week ago I posted a few pictures of my hydrangeas. Little did I know it would garner so much attention! I am thrilled you are interested, asking questions, and waiting for answers, no doubt. Here they are!
When to Prune
Pruning at the wrong time can leave you with a leafy shrub and no flowers. Not fun at all. I will categorize hydrangeas into two very broad groups: those that bloom on old wood and those that bloom on new wood.
- Blooming on Old Wood
If your hydrangea blooms on old wood, you should prune as flowers begin to drop and fade. Blooms are set in the fall and pruning in the spring will remove all of these blooms that are raring to go come spring. Pruning in the fall must be done carefully as your plant still needs time to recover before winter hits. The sooner the better for these plants.
2. Blooming on New Wood
If your hydrangea blooms on new wood, you should practice late winter pruning (i.e. now). Blooms will set on the new spring growth and pruning now will initiate some quick spring growth. You’d be hard-pressed to prune these plants at the wrong time. Unlike hydrangeas that bloom on old wood, new wood bloomers can bounce back from just about anything.
How to Tell
Hydrangeas that bloom on old wood typically bloom early in the season (late spring – early summer) and blooms don’t last too long (until mid to late summer).
Hydrangeas that bloom on new wood bloom a little later (midsummer) and will bloom right up until the frost hits in the fall.
If you’re still unsure about your hydrangea, check out this visual guide at Hydrangeas! Hydrangeas!
A quick and easy guide for pruning:
Mophead: late summer pruning
Lacecap: late summer pruning
Oakleaf: late summer pruning
Panicle: late winter pruning
Annabelle: late winter pruning
How to Prune
Now for the hands-on work: pruning.
- Blooming on Old Wood (Late Summer Pruning)
Step 1: Remove dead branches
Step 2: Cut back 1/3 of the plant to the ground if it has been planted at your house for 5 years or longer
Step 3: Prune for size or shape
When pruning these hydrangeas, be very aware of the stage it’s at. Pruning too late into the fall will leave you with a flower-less plant next summer.
2. Blooming on New Wood (Late Winter Pruning)
Annabelles: I cut my Annabelle hydrangeas down to the ground every winter. They grow back with vigour in the spring and summer and it keeps them from getting too big.
Panicles: The only type of hydrangea that can be shaped into a tree: prune it that way if you wish! Or don’t. It’s up to you. If you want the hydrangea tree look, you’ll need to keep the main stem (just like any other tree). Top branches should be untouched. Criss-crossing branches should be removed to keep air flow and sunlight from reaching into the tree.
If you didn’t prune your old-wood hydrangea last fall, don’t stress! You’ll get lots of blooms this summer – just put it on your to-do list for August.
If you haven’t pruned your new-wood hydrangea yet, you’re running out of time – get to it this weekend! Do a quick peek around the plant first to check for blossoms…stop immediately and put the task in your calendar for next February / March.
Have fun! Spring is here and we are ready for it.
